#coding=utf-8
from stutils import *
set_django_environ()
from stdj.stock.models import *

def prices_on(exdate):
    eds = Exday.objects.filter(date=exdate)
    if eds.count == 0:return None
    return [e.price for e in eds]

def changes_on(exdate):
    ps = prices_on(exdate)
    if not ps:return None
    
    return [float(p.change) for p in ps]

def medi